Diaphragms are structures attached to the ends of adjacent railroad cars (or railcars) to provide an enclosed space between the adjacent railcars that permits passengers to conveniently move from one railcar to the other. Diaphragms protect passengers from the environment and/or from noise when the passengers move between railcars. Moreover, diaphragms are constructed such that they can absorb forces produced by the moving train when, for example, the train is navigating a curve at a relatively high speed. In the past, diaphragms were large, expensive structures with walls of solid resilient material coated with a sealing polymer and contoured to permit expansion, contraction, and/or torsional movement of the diaphragms with respect to each other and with respect to the railcars during movement of the train.
More recently, a diaphragm is typically made of a flexible material, such as a reinforced molded rubber material that surrounds the door of the railcar and at the other end is attached to face plates. This molded rubber material not only protects passengers from the weather and/or from noise, but it can also absorb the forces produced by the moving train during normal train operations. The face plates of adjacent railcars carry wear plates that abut each other when the railcars are engaged. These face plates can be replaced once they wear out, extending the life of the diaphragm. Step or walk plates are also provided over which the passengers can walk when passing through the diaphragm from one railcar to another.